In addition to the correction of low-order aberrations, we implemented several speckle control techniques such as speckle nulling[1]}, electric field conjugation (EFC), Linear Dark Field Control (LDFC)[2]}, necessary to reach deeper contrasts by correcting high-order aberrations unseen by the PyWFS. Their on-sky implementation was proven quite difficult, as they tend to require a very stable wavefront correction, and a good calibration of the PyWFS. For on-sky implementation, we have been using fast infrared cameras such as the C-RED1, the C-RED2, and the MEC. We also tested less conventional speckle nulling algorithm, such as the multi-star wavefront control (MSWC)[3]}, a speckle nulling algorithm used for binary systems. Finally, we demonstrated the LDFC algorithm to stabilize the dark hole over longer periods of time, notably by measuring the disturbances using the opposite bright field. Figure REF  shows the results of the speckle nulling, the EFC, and the LDFC algorithm. Especially, the laboratory demonstration of the EFC is uploaded on the YouTube channel of the SCExAO team (see https://youtu.be/ppQupxlmi8U). These collaborations are helping solve new challenges that will face future high-contrast imaging systems, and therefore are essential for reaching the contrast necessary to detect earth-like planets with ELTs.
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